1. Field of the Invention
A mobile heater for railroad rails of simple yet highly effective construction giving high efficiency, portability and adaptability for use on railroad tracks of different or varying gauges. Also, it is concerned with a method for heating and expanding rails with a mobile rail heater mounted on wheels and having a series of gas burners mounted under a heat shield and connected to compressed gas bottles. The mobile rail heater is adapted to roll along a pair of railroad rails and to heat one of the rails on which it is carried.
2. Description of the Prior Art
Railroad rails laid on timbers are well known to everyone as the roads on which railway trains have travelled through this country for over a century. Some of the rails, varying from 30 feet to one-fourth mile in length, have been subject to stress and fatigue through usage, for years. In the past, the rails were welded together at their joints, while present practice is to use large bolts and plates to connect the rails at the joints. When the rails are at ambient temperature it is desirable that each rail be somewhat in tension along its length.
When a rail fails from stress or fatigue or a joint must be repaired or replaced, the length of the rail must be increased from 1/4"to 4" depending on the difference between the rail length and the distance between the adjacent rails. While the rail might conceivably be drawn manually by clamps or the like, it is impractical to do so because of the great tensile strength of the iron rail.
It has been the practice to heat the rail to cause it to expand. The heating of the rail has heretofore been accomplished by soaking ropes in a fifty-five gallon drum of diesel fuel, with a rope then being laid on each side of the web of a rail and then ignited. The ropes usually burn for up to three hours, following which the process must be repeated in the event the rail has not sufficiently expanded. In winter climates, the burning rope will not heat the rail sufficiently to expand it and thus no new rail may be laid during this period.